rxeighth

Hi,

I have a 2004 RX8 with single disc Bose system. Very long time lurker but registered to finally post.

On a very cold day my battery decided to die. I jump started it, but my head unit no longer turns on and the LCD Display is not working (it is completely blank). The Heater/AC unit works completely fine. I've replaced the battery. I've looked over the forums to try to diagnose the issue but at this point I'm completely stuck.

Things I've checked:

I checked all of the fuses visually and with a multimeter to confirm that the Radio and ACC fuses have both continuity and proper voltage.

I checked the electrical harness that plugs into the Bose Head Unit to make sure that the 'Power Supply +B' pin was getting 12V, the 'Power Supply / ACC' pin was getting 12V, and the 'P Ground' pin was working as a proper ground. For reference to the pins I'm talking about please see this diagram:
https://www.rx8club.com/showpost.php...42&postcount=7

I know it is common for the faceplate to disconnect from the head unit, but I am sure mine is connected. At one point I completely stripped the faceplate down to just the PCB (removed all of the plastic parts) to make 100% sure it was connected to the Head Unit and pushed all of the way in. I've also read on the forums that if this is the actual problem then you can eject a CD that's currently in the player. I have a CD stuck in there that won't eject.

I assumed that I needed a replacement head unit, so I ordered a used 2005 6-CD Bose head unit/faceplate combo from an Ebay Autoparts seller. And this unit has the exact same issue.

The only thing I can think of is the Ebay seller sold me a unit with the exact same problem... but I don't really think it's a coincidence.

I finally took the thing into the dealership and they said they were sure that the head unit was bad and needed to be replaced (after charging me $100 for the diagnosis...). They quoted me over $1100 for just the parts! So that's not an option.

Any advice or suggestions would be greatly, greatly appreciated.

Thanks,

monchie

For what i just read...just replace it with a new one.

DeViLbOi

iTrader: (1)

Before ordering a new one...find a local and swap radios back and forth...I doubt that you have two bad radios. When you tested for voltage at the harness did you test the front or back of the harness? Also have you tested for constant voltage at the first point within the radio?

rxeighth

I just test the harness at the front where it connects to the pins on the head unit.

I will strip down the head unit to the PCB and test the constant voltage the the first point within the radio as soon as I can. Thank you for the suggestion.

I put up a post in the NE Forums to try and find someone in the Rochester, NY area that might be willing to swap radios with me.

Thanks again.

rxeighth

I am having trouble figuring out how I can hook the radio up to my car and test for the constant voltage at the first point in the radio. Would I just strip the radio down to the basic PCB with nothing but the electrical harness attached? (no faceplate or heating unit)

If any one is within a few hours or Rochester, NY and would be willing to do a radio swap with me to test my radio let me know. I will pay for your time. I also have family in Boston, MA & Hartford, CT so if you live near those areas and are willing to do a radio swap this weekend please let me know. I am currently jobless so I could drive down almost any time. It shouldn't take more than an hour of your time and it would greatly help me figure out what the heck is wrong with my car.

DeViLbOi

iTrader: (1)

In theory you could hook up constant, switched and ground to a 12V power source and test it.

Sisco360

I had a similar problem. They replaced the entire unit. Covered under warranty at the time. Now I have to stick my golf divot tool in the heater **** to get heat (about 30,000 miles later). Seems like the entire unit is garbage on 04's-05-s. RX-8 is like having another grilfriend, bitchy and high maintenence as hell.

Rote8

But oh, what a ride....

rxeighth

So, I tried my 3rd replacement head unit today. The first time I plugged the unit in it worked fine when I turned on the car, but after that first working time now it keeps having the same problem of my other unit. (LCD/radio do not come on).

I'm completely stuck on what the issue is. could my car be frying head units? what could possibly cause this? The stereo and ACC fuses are fine... i just checked the voltage on them.

Anyone have any idea what the issue is?

WhiteCross

iTrader: (1)

rxeighth I am having the same issue as you are with my '04, I just purchased a second head unit and had the local shop switch it for me but still have the same issues....I am at a complete loss....The only thing I am thinking of doing is going ahead and getting the metra kit and being done with it altogether.

rxeighth

keep me updated if you end up getting the metra kit and let me know if it works out. I tried 2 replacement head units so far so I think I'm just going radio-less for now. It's so weird because I'm 100% sure that I have a good ground wire, constant 12V, and switched 12V because of the multimeter testing I've done on the front of the electrical harness.

I'm a little concerned that maybe the metra kit won't even work if it's some sort of weird short going on...

all i want is some radio in my car, lol

DeViLbOi

iTrader: (1)

Have you verified that you don't have an issue with one of the Bose amps being shorted and returning voltage to the headunit?

rxeighth

Hi DeViLbOi,

Thank you for the suggestion. I just unplugged the Bose Amp in back and that didn't change anything. Thank you again though for the thought. I'm thinking about having an audioshop double check my harness and maybe install a new one from the battery as a last resort.

WhiteCross

iTrader: (1)

Hmm...do you think it could be the electronics in the front panel itself that are bad? I talked to another car audio shop they had no luck with the swap either and said it could be some other unit that (forgive my ignorance) provides power/controls the LCD. He said it is located in the glove box area...does any of this sound accurate? or does the guy not know what he is talking about?

rxeighth

I'm not sure what unit they were talking about. I was under the impression that power went to the radio from:
Battery -> Fuse Box(under hood) -> Fuse Box(near foot of door) -> Head Unit

I tried to trace the ground wire. it looks like that goes to somewhere near the glove box. Could that be what they are talking about?

I want to double check the head unit ground, but I am having a really difficult time tracing where the wire eventually connects to the frame of the car. Any one have an idea where this ground is supposed to ground to the car?

zoom44

https://www.rx8club.com/series-i-trouble-shooting-95/radio-wont-turn-lcd-wont-light-up-ac-wont-work-213779/

you both have/had stuck CDs and the same issue....

rxeighth

His issue is a little different than mine. He has no AC/heat which indicates a faceplate connection issue. I know my faceplate connection is fine because I've stripped the faceplate down to just the PCB and tested it. Plus my AC/heat works fine and it wouldn't work at all or just the fan would work if there was a faceplate problem.

WhiteCross

iTrader: (1)

Just a quick bump to see if any new info has surfaced....

rxeighth

I retested all of my connections today. checked fuses, faceplate, and what I think are the grounds on the cars chassis. still nothing.

Best Buy told me they could test my double DIN connector for free so I'm going to set up an appointment to do that in the next week or so. I'm considering paying an audio install place to put a brand new electrical harness straight from the battery to the head unit. At this point I feel like it's the only option to get a radio going.

DeViLbOi

iTrader: (1)

Won't help if the extra voltage is coming from one of your Bose amps though. Find the cause...then address...don't try to address random possibilities without even the smallest amount of data to back it up.

rxeighth

I just now realized that the two door amps are connected directly to the head unit. For some reason I thought they connected to the rear amp first. I did unplug the rear amp so I know that's not causing it. What is the best way to test the door amps/speakers for a short? Do you take the door apart and unplug them?

WhiteCross

iTrader: (1)

Would you have gotten anyone to test your unit(s) in their car? I tried to get someone in the KC area in the regional forum but haven't had any luck with a response. This new car thing with no music is starting to get to me...

DeViLbOi

iTrader: (1)

Yes...you need to take the door apart to get to the door amps.

WhiteCross

iTrader: (1)

Bump for Sunday, I'm still stuck with the same issue. Wondering if any new info has surfaced...

rxeighth

Hey, I still haven't had a chance to unplug my door amps. I've had an insane stomach flu for the last week

...so I haven't really worried about my radio. I should be able to test the amps in the next couple days though and I'll let you guys know the results either way.